Jan., 1911 
Till-: I’AIJJl) \VR]':X-TIT 
,11 
found nesting in the sage {Arfcmcsia) of the lowland country. The nest, in both 
location and construction, is not in the least wTat the uninitiated oologist would 
expect in this type of bird. The first one I ever saw was building and, no birds 
being present, I felt sure it must belong to some kind of flycatcher that had es- 
caped my notice, so closely did it resemble certain types of nests of the Traill 
Flycatcher {Eiiipidoiiax trailli irailli) that I have found. It was a perfecth' 
typical nest, both in location and construction, being placed about one foot from 
the ground in the crotch of a live-oak bush that stood in a dense thicket of the 
same. It is built externally of silkv plant fibres, fine strips of bark and fine dead 
grass, the lining being mostly of horse hair. The measurements are externally four 
inches in diameter, by a little less than three inches in depth; internal dimensions 
being two and one-quarter inches wide, by one and three-quarters deep. I have 
seen one nest as high as five feet above the ground, but this is most unusual, three 
feet up being considerably higher than the average. 
The eggs in all the nests that I have examined were invariably four in number 
to the set. They are most attractive in appearance, being greenish blue in color, 
without markings of any kind. In shape they are a rounded-oval, as a rule, aver- 
aging in size about .74 X..t 7 inches. 
The female appears to commence covering the eggs much of the time before 
the set is completed, as on two occasions I have found the bird sitting on three 
eggs, to which a fourth w^as added on the day following. Even under these cir- 
cumstances the bird is exceedingly loath to leave the nest, and after incubation com- 
mences it is necessary to startle her very considerably, or remove her by hand, in 
order to examine the contents of the nest. She will then very often remain in the 
same bush, scolding in a low, harsh ch-ch-ch, continuousl\- and very rapidly re- 
peated. This usually brings up the male, wdio looks over tlie situation for a 
moment or two and then returns to his singing, feeling apparently not the least 
sympathy with the vigorous protests of his mate. I have noticed tliis habit in sev- 
eral other varieties of birds, and have often asked myself if it might not, instead of 
lack of sympathy, be another method of endeavoring to draw the attention of an 
intruder away from the nest. 
COLLECTING SOCORRO AND BLACK PblTRELS IN LOWER CALIFORNIA 
By PIXC.KID': I. OSIJURX 
WITH TWO PHOTOS 
T his Genus of birds ( Occauodronia) is to the author one of unusual interest. 
Every available opportunity that has come my way for five years past has 
been made use of to become better acquainted with sea fowl in general and 
the Petrels in particular. For this reason the Los Coronados Islands were visited 
several times in recent years, each stay consisting of from one day to two weeks. 
While I w'as disappointed by not finding these particular birds on all my trips, the 
entire number of days ashore in active work among their burrows would number a 
satisfactory total. 
The two trips of most importance were on July 3, 1909 (the third trip), and 
June 19 of the present year (the sixth trip). The first was in company with Mr. 
Willis Ritchie, and the second with Mr. A. B. How'ell. I wish to hereby acknowl- 
